Allocation of Communication Resources

ABSTRACT

The disclosure relates to allocation of resources for wireless communications. An index for an uplink control resource is determined in accordance with a predefined rule. The determining takes into account an index associated with a physical downlink resource and the amount of downlink resources to be mapped on the uplink control resource.

This disclosure relates to allocation of resources for communicationsand more particularly but not explicitly to allocation of resources foruplink control signals for wireless communications.

A communication system can be seen as a facility that enablescommunication sessions between two or more nodes such as fixed or mobiledevices, machine-type terminals, access nodes such as base stations,servers and so on. A communication system and compatible communicatingentities typically operate in accordance with a given standard orspecification which sets out what the various entities associated withthe system are permitted to do and how that should be achieved. Forexample, the standards, specifications and related protocols can definethe manner how devices shall communicate, how various aspects ofcommunications shall be implemented and how devices for use in thesystem shall be configured.

Users can access the communication system by means of appropriatecommunication devices. A communication device of a user is oftenreferred to as user equipment (UE) or terminal. A communication deviceis provided with an appropriate signal receiving and transmittingarrangement for enabling communications with other parties. Typically adevice such as user equipment is used for enabling receiving andtransmission of communications such as speech and content data.

Communications can be carried on wireless carriers. Examples of wirelesssystems include public land mobile networks (PLMN) such as cellularnetworks, satellite based communication systems and different wirelesslocal networks, for example wireless local area networks (WLAN). Inwireless systems a communication device provides a transceiver stationthat can communicate with another communication device such as e.g. abase station of an access network and/or other user equipment. The twodirections of communications between a base station and communicationdevices of users have been conventionally referred to as downlink anduplink. Downlink (DL) can be understood as the direction from the basestation and uplink (UL) the direction to the base station.

Various control information may need to be signalled between theparties. Control information is typically communicated on controlchannels, for example on physical uplink control channel (PUCCH) orphysical downlink control channel (PDCCH). For example, informationrelating to resource may need to be signalled between stations.Allocation of resources for the downlink and the uplink can be handledindependently. Uplink (UL) assignments or grants sent to a userequipment (UE) are used to inform the user equipment of resources the UEshall use to transmit data. Information when anything might be expectedin the downlink may also be communicated from a base station. By meansof the grants dynamic allocation of resources can be provided.Signalling of other types of control information is also needed. Forexample, a user equipment may need to signal feedback information on theuplink. Feedback information can be provided for the purposes of errordetection and/or correction. Requests for retransmission of anyinformation that the recipient node did not successfully receive arepossible. For example, hybrid automatic repeat request (HARQ) errorcontrol mechanism may be used for this purpose. The error controlmechanism can be implemented such that a transmitting device shallreceive either a positive or a negative acknowledgement (ACK/NACK; AIN)or other indication regarding its transmission from a receiving device.

Increased utilization of advanced systems for various scenarios anddifferent data traffic types increases the need to optimize the systemfurther for a large number of users. A way to achieve this is to improvescheduling efficiency. In particular, reduction in scheduling overheadmay be desired. It might be desired in certain applications to reducedownlink control signalling overhead caused by uplink and downlinkscheduling. Optimization of signalling on physical downlink controlchannel (PDCCH) could be of particular advantage. For example, currentlyPUCCH resource allocation for PDSCH ACK/NACK is based on implicitmapping where the index of the lowest PDCCH Control Channel Element(CCE) determines directly the index of the PUCCH resource. Such“one-to-one” mapping provides a relatively efficient resource allocationscheme for a number of active UEs as dedicated ACK/NACK channels are notneeded for each of them. Instead, the channels can share a commonresource space which has the same size as the number of downlink CCEs.However, increased multiplexing of different users increases the numberof possible downlink control channels. On particular, if differenttechnologies, for example code division multiplexing (CDM) and frequencydivision multiplexing (FDM) are used, the number of possible downlinkcontrol channel candidates increases. This may be particularly the casewith enhanced physical downlink control channels (ePDCCH). Furthermore,techniques such as multi-user multiple input multiple output (MU-MIMO)scheduling may be enabled for ePDCCH, and this in turn may increase thenumber of possible ePDCCH candidates in a cell, possibly up to severalhundreds. In such situation one-to-one indexing of all the possibleePDCCH candidates could easily lead to an excessive number of ACK/NACKchannels, and hence uplink overhead. Therefore there is a need for amore efficient indexing system for uplink control resource allocation,for example for PUCCH ACK/NACK resource allocation in case of ePDCCHscheduling such that collisions can be avoided.

It is noted that the above discussed issues are not limited to anyparticular communication environment and station apparatus, but mayoccur in any appropriate station apparatus where internal communicationsare required.

Embodiments of the invention aim to address one or several of the aboveissues.

In accordance with an embodiment there is provided an apparatus forallocation of resources for wireless communications, the apparatuscomprising at least one processor, and at least one memory includingcomputer program code, wherein the at least one memory and the computerprogram code are configured, with the at least one processor, todetermine an index for a uplink control resource in accordance with apredefined rule, the determining taking into account an index associatedwith a physical downlink resource and the amount of downlink resourcesto be mapped on the uplink control resource.

According to another aspect, there is provided a method for allocationof resources for wireless communications, the method comprisingdetermining an index for a uplink control resource in accordance with apredefined rule, the determining taking into account an index associatedwith a physical downlink resource and the amount of downlink resourcesto be mapped on the uplink control resource

According to a more detailed aspect, the lowest index of the physicaldownlink resource block is taken into consideration.

The index associated with the physical downlink resource may comprise atleast one of an index of an enhanced control channel element, an indexof an enhanced physical downlink control channel and an index of aphysical downlink shared channel scheduled by means of an enhancedphysical downlink control channel.

An offset may be used in determining the index for the uplink controlresource. At least one of an antenna port indicator and a scramblingidentity may be used in in defining the offset. An offset parameter maybe signalled in the downlink. The offset may be used for dynamicswitching between at least two physical uplink control channel (PUCCH)format 1/1a/1b resources.

The amount of downlink resources is indicative of a number of downlinkphysical resource blocks that map to a physical uplink control channelresource.

Indications of the amount of downlink resources may be processed basedon a configurable parameter. Information about the amount of downlinkresources may be signalled in a user equipment specific or cell specificmanner.

The downlink resource may comprise a physical downlink shared channel.Scheduling information for the physical downlink shared channel may becommunicated by means of an enhanced physical downlink control channel.An index for a physical uplink control channel associate with thephysical downlink shared channel may be determined. At least one indexfor signalling of automatic repeat request messages may be determined.

A final index for the uplink control resource may be defined by applyingat least one further operation to an index determined based on an indexassociated with a physical downlink resource and the amount of downlinkresources to be mapped on the uplink control resource.

A node such as a base station or a communication device of a user ofmachine type terminal can be configured to operate in accordance withthe various embodiments.

A computer program comprising program code means adapted to perform themethod may also be provided. The computer program may be stored and/orotherwise embodied by means of a carrier medium.

It should be appreciated that any feature of any aspect may be combinedwith any other feature of any other aspect.

Embodiments will now be described in further detail, by way of exampleonly, with reference to the following examples and accompanyingdrawings, in which:

FIG. 1 shows a schematic diagram of a communication system comprising abase station and a plurality of communication devices;

FIG. 2 shows a schematic diagram of a mobile communication deviceaccording to some embodiments;

FIG. 3 shows a schematic diagram of a control apparatus according tosome embodiments;

FIGS. 4 and 5 show flowcharts according to certain embodiments; and

FIGS. 6 to 8 show tables relating to parameters of particular examples.

In the following certain exemplifying embodiments are explained withreference to a wireless or mobile communication system serving mobilecommunication devices. Before explaining in detail the exemplifyingembodiments, certain general principles of a wireless communicationsystem, access systems thereof, and mobile communication devices arebriefly explained with reference to FIGS. 1 to 3 to assist inunderstanding the technology underlying the described examples.

An example of wireless communication systems are architecturesstandardized by the 3rd Generation Partnership Project (3GPP). A latest3GPP based development is often referred to as the long-term evolution(LTE) of the Universal Mobile Telecommunications System (UMTS)radio-access technology. The various development stages of the 3GPP LTEspecifications are referred to as releases. More recent developments ofthe LTE are often referred to as LTE Advanced (LTE-A). The LTE employs amobile architecture known as the Evolved Universal Terrestrial RadioAccess Network (E-UTRAN). Base stations of such systems are known asevolved or enhanced Node Bs (eNBs) and may provide E-UTRAN features suchas user plane Radio Link Control/Medium Access Control/Physical layerprotocol (RLC/MAC/PHY) and control plane Radio Resource Control (RRC)protocol terminations towards the communication devices. Other examplesof radio access system include those provided by base stations ofsystems that are based on technologies such as wireless local areanetwork (WLAN) and/or WiMax (Worldwide Interoperability for MicrowaveAccess).

A device capable of wireless communications can communicate via at leastone base station or similar wireless transmitter and/or receiver node.In FIG. 1 a base station 10 is shown to be serving various mobiledevices 20 and a machine-like terminal 22. Base stations are typicallycontrolled by at least one appropriate controller apparatus so as toenable operation thereof and management of mobile communication devicesin communication with the base stations. The base station can beconnected further to a broader communications system 12. It shall beunderstood that a number of neighbouring and/or overlapping accesssystems or radio service areas provided by a number of base stations mayexist. A base station site can provide one or more cells or sectors,each sector providing a cell or a subarea of a cell. Each device andbase station may have one or more radio channels open at the same timeand may send signals to and/or receive signals from one or more sources.As a plurality of devices can use the same wireless resource,transmissions thereof need to be scheduled to avoid collisions and/orinterference.

A possible mobile communication device for transmitting in uplink andreceiving in downlink will now be described in more detail withreference to FIG. 2 showing a schematic, partially sectioned view of acommunication device 20. Such a communication device is often referredto as user equipment (UE) or terminal. An appropriate communicationdevice may be provided by any device capable of sending radio signals toand/or receiving radio signals. Non-limiting examples include a mobilestation (MS) such as a mobile phone or what is known as a ‘smart phone’,a portable computer provided with a wireless interface card or otherwireless interface facility, personal data assistant (PDA) provided withwireless communication capabilities, or any combinations of these or thelike. A mobile communication device may provide, for example,communication of data for carrying communications such as voice,electronic mail (email), text message, multimedia and so on. Users maythus be offered and provided numerous services via their communicationdevices. Non-limiting examples of these services include two-way ormulti-way calls, data communication or multimedia services or simply anaccess to a data communications network system, such as the Internet.Non-limiting examples of content data include downloads, television andradio programs, videos, advertisements, various alerts and otherinformation.

The device 20 is configured to receive signals in the downlink 29 overan air interface via appropriate apparatus for receiving and to transmitsignals in the uplink 28 via appropriate apparatus for transmittingradio signals. In FIG. 2 the transceiver apparatus is designatedschematically by block 26. The transceiver apparatus 26 may be providedfor example by means of a radio part and associated antenna arrangement.The antenna arrangement may be arranged internally or externally to themobile device.

A mobile communication device is also provided with at least one dataprocessing entity 21, at least one memory 22 and other possiblecomponents 23 for use in software and hardware aided execution of tasksit is designed to perform, including control of access to andcommunications with base stations and/or other communication devices.The data processing, storage and other relevant apparatus can beprovided on an appropriate circuit board and/or in chipsets. Thisapparatus is denoted by reference 24.

The user may control the operation of the mobile device by means of asuitable user interface such as key pad 25, voice commands, touchsensitive screen or pad, combinations thereof or the like. A display 27,a speaker and a microphone can be also provided. Furthermore, acommunication device may comprise appropriate connectors (either wiredor wireless) to other devices and/or for connecting externalaccessories, for example hands-free equipment, thereto.

FIG. 3 shows an example of a control apparatus 30 for a communicationsystem, for example to be coupled to and/or for controlling a basestation. In some embodiments a base station may comprise an integratedcontrol apparatus and some other embodiments the control apparatus canbe provided by a separate network element. The control apparatus can beinterconnected with other control entities. The control apparatus andfunctions may be distributed between a plurality of control units. Insome embodiments each base station can comprise a control apparatus. Inalternative embodiments, two or more base stations may share a controlapparatus. The arrangement of the control depends on the standard, andfor example in accordance with the current LIE specifications noseparate radio network controller is provided. Regardless the location,the control apparatus 30 can be understood as providing control oncommunications in the service area of at least one base station. Thecontrol apparatus 30 can be configured to provide control functions inassociation with scheduling of uplink in accordance with embodimentsdescribed below. For this purpose the control apparatus can comprise atleast one memory 31, at least one data processing unit 32, 33 and aninput/output interface 34. Via the interface the control apparatus canbe coupled to a base station to cause operation of the base station inaccordance with the below described embodiments. The control apparatuscan be configured to execute an appropriate software code to provide thecontrol functions.

A wireless communication device, such as a mobile device, machine-liketerminal or a base station, can be provided with a MultipleInput/Multiple Output (MIMO) antenna system. MIMO arrangements as suchare known. MIMO systems use multiple antennas at the transmitter andreceiver along with advanced digital signal processing to improve linkquality and capacity. For example, the transceiver apparatus 26 of FIG.2 can provide a plurality of antenna ports. More data can be receivedand/or sent where there are more antennae elements.

In accordance with an embodiment an implicit indexing scheme for uplinkcontrol channels resources is provided. A method of providing uplink(UL) indices in an user equipment is illustrated by the flowchart ofFIG. 4. A downlink (DL) assignment of resources for wirelesscommunications by at least one user equipment as allocated by a networkelement, for example an eNB, is received at 40. Thus information aboutscheduled downlink resources is provided on a physical downlink controlresource for the user equipment at this stage. An index for uplinkcontrol resource in accordance with a predefined rule can be determinedat 42. The determining takes into account an index associated with aphysical downlink resource and the amount of downlink resources to bemapped on the uplink control resource. A control message associated withthe DL assignment can then be transmitted at 44 on the determinedresource.

In accordance with an embodiment the downlink index associates with anenhanced physical downlink control channel (ePDCCH) or a physicaldownlink shared channel (PDSSC) scheduled by means of an enhancedphysical downlink control channel. The index may be the lowest index ofthe physical downlink resource block. According to a possibility theindex comprises the lowest index of an enhanced control channel element.The control message may comprise ACK/NACK for the PDSCH on a determinedphysical uplink control channel (PUCCH) resource.

An offset may be used at 42 in determining the index of the uplinkcontrol resource to avoid collisions. The offset can be used to enabledynamic switching between different PUCCH format 1/1a/1b resources bymeans of the offset. Thus the offset can be used to select anappropriate resource among the available resource sets.

FIG. 5 illustrates the operation at the network side. An appropriatecontroller, for example an eNodeB (eNB) determines the UL resource sothat it knows on which resource to receive the control messages. TheeNodeB can perform this for example when it allocates DL resources, forexample ePDCCH and PDCHS resources, at 50. The DL assignment can then besent at 52. The network element can expect to receive the controlmessages at 54 in accordance with the predefined rule.

In accordance with an example HARQ resources can be allocated on aphysical uplink control channel (PUCCH) when enhanced physical downlinkcontrol channel (ePDCCH) is used to schedule downlink data on a physicaldownlink shared channel (PDSCH). ePDCCH is a recent development of theLTE and is designed to improve control channel performance. ePDCCH maybe in particular useful in connection with arrangements such ascoordinated multipoint (CoMP), DL MIMO, heterogeneous networks (HetNet)and carrier aggregation, including use of extension carriers. Forexample, ePDCCH may be used to provide support for increased controlchannel capacity, support for frequency-domain interference control andinterference coordination (ICIC), improved spatial reuse of controlchannel resources, support for beamforming and/or diversity, support foroperation on new carrier types and in Multicast Broadcast SingleFrequency Network (MBSFN) subframes, capability to coexist on the samecarrier as legacy user equipment, ability to be scheduledfrequency-selectively, ability to mitigate inter-cell interference andso on.

By means of an implicit mapping rule an index for the uplink controlresource can be derived based on the index of a relevant downlinkchannel. The rule does not need to consider the exact PUCCH resource therelevant control message associated with the downlink shall map to. Bymeans of the embodiment many-to-one implicit indexing can be providedand collisions of indices may be avoided in the case of multiuserarrangements such as MU-MIMO. The many-to-one mapping from downlinkresource blocks to the uplink channel may be configurable.

In accordance with an embodiment where ePDCCH is used to scheduledownlink data on PDSCH uplink control channel resource(s) for thefeedback mechanism are provided in response to a received PDSCH. Moreparticularly, indexing of ePDCCH resources for supporting implicitresource allocation for HARQ ACK/NACK is provided. An implicit resourceallocation rule can be provided for the HARQ-ACK resources correspondingto PDSCH scheduled via ePDCCH.

In the example below a new uplink index parameter, denoted asn_(ePDCCH→PUCCH) ⁽¹⁾, is defined. The exemplifying index parametercorresponds to a PUCCH Format 1/1a/1b channel. The parameters that maybe used to determine n_(ePDCCH→PUCCH) ⁽¹⁾ include physical resourceblock (PRB) compression factor (granularity). This parameter can be usedto define the number of PUCCH resources per DL PRB, i.e. how many DLePDCCH or PDSCH PRBs map to a single PUCCH resource. The physicalresource block can be consecutive. Physical resource block (PRB)compression factor provides a many-to-one mapping between the scheduledDL resource (ePDCCH or PDSCH) and the PUCCH resource used for HARQ-ACKtransmission and allows to adjust the number of PUCCH resources reservedto PDSCH scheduled via ePDCCH.

Instead of a physical resource block, the compression by mapping anumber of DL resources in a lesser number of UL resources may also bedone similarly e.g. with respect to enhanced control channel elements(eCCEs).

An offset parameter can also be used to define a dynamic offset for thePUCCH Format 1/1a/1b resource domain. The offset parameter can be usedto allow facilitation of dynamic switching among plurality of PUCCHFormat 1/1a/1b channels to avoid n_(ePDCCH→PUCCH) ⁽¹⁾ collisions causedby PRB compression. This can be particularly the case in many-to-onemapping and e.g. MU-MIMO scheduling. In accordance with a possibleresource allocation scheme the existing parameters, namely antenna portindicator and scrambling identity (nSCID) are used as parameters todefine the offset. According to a possibility an explicit valueindicated in the downlink control information (DCI) may be used indefining the offset. This provides eNBs with the option of making asimple shift to avoid collisions in the uplink control channel domain.Existing parameters and the explicit offset indication can also be usedin combination in defining the offset.

As an example, antenna port and scrambling identity (nSCID) for LTE asdefined by Table 5.3.3.1.5C-1 of 3GPP Technical Specification (TS)36.212, is reproduced in Table 1 in FIG. 6.

The existing signaling can be reused as such to avoid n_(ePDCCH→PUCCH)⁽¹⁾ collisions due to MU-MIMO. In the case of MU-MIMO scheduling eNB canmake e.g. the following MU-MIMO pairing:

-   -   the first UE: 1 layer port 7, nscid=0    -   the second UL: 1 layer port 8, nscid=1

Table 2 of FIG. 7 shows how different combinations of lowest antennaport and scrambling identity parameters selectable by an eNB each cangive a different offset parameter. Thus different PUCCH resources can beoccupied by defining the offset based on the existing parameters.

An example of an index associated with the physical downlink resource isa parameter defining the lowest PRB index of ePDCCH or a PDSCH scheduledvia ePDCCH.

A specific mapping rule can be defined for many-to-one mapping betweenthe input parameter and the PUCCH format 1a/1b channel. In accordancewith an example the mapping can be defined as:

n _(ePDCCH→PUCCH) ⁽¹⁾=└PRB 1st×granulalarity┘+offset

where:└ ┘ is a floor operation,PRB_(—)1st is the index of the lowest PDSCH or ePDCCH PRB when PDSCH isscheduled via ePDCCH,granularity is a parameter defining the number DL PRBs mapping to asingle PUCCH resource, andoffset is an offset parameter which depends on the lowest antenna portand scrambling identity according to Table 2, see FIG. 7.

Instead of physical resource blocks, other resources, for exampleenhanced control channel element, may be used as a base for theindexing.

It is noted that a given resource index (n_(ePDCCH→PUCCH) ⁽¹⁾) may besubject to further mathematical operations to define the final index forPUCCH Format 1/1a/1b channel. These may include operations such asaddition of semi-static offset (this allows to shift ePDCCH resourceswithin the existing PUCCH Format 1/1a/1b resource space) and furtherdynamic modifier such as ARI (ACK/NACK resource index) included in theDCI, allowing the eNB to select one out N resources available.

The granularity is a configurable parameter. In accordance with anembodiment granularity parameter is configured via radio resourcecontrol (RRC) signalling either in cell-specific manner or inUE-specific manner. Currently values [1, 2, ½, ¼, etc.] are consideredappropriate for the granularity parameter, but other values may also beconsidered. The granularity parameter can be understood as the spacingin terms of PUCCH resources derived based on two consecutive DL PRBs(either ePDCCH or PDSCH). A granularity value <1 implies many-to-onemapping (compression), i.e. several DL PRBs map to a single PUCCHresource.

Tables 3A and 3B in FIG. 8 shows two examples for n_(ePDCCH→PUCCH) ⁽¹⁾mapping as a function of PRB_(—)1^(st) and offset. In the first exampleof Table 3A granularity parameter is set to ¼ and the offset fordifferent PRB_(—)1^(st) values varies from 0 to 4. This results uplinkindex values from 0 to 9. In the second example of Table 3B granularityis set to 2, the offset varying from 0 to 4. In this example uplinkindices vary from 0 to 51.

The embodiments may provide a scalable solution for the PUCCH resourcedimensioning. This can be used to allow to trade-off between schedulerflexibility and PUCCH overhead. Existing parameters such as antenna portand scrambling indicator can be utilised in handling a MU-MIMO scenario.In a particular embodiment ePDCCH scheduling (e.g. search space and linkadaptation) can be kept independent from PUCCH resource allocation. Thiscan simplify the scheduler operation. It is also an advantage that thesame NN resource pool can be used for PUCCH HARQ ACK/NACKs for legacyuser equipment and ePDCCH enabled user equipment.

It is noted that whilst embodiments have been described in relation toLTE, similar principles can be applied to any other communication systemor to further developments with LTE. Also, instead of scheduling that isprovided by a control apparatus associated with a base stationscheduling may be provided by any apparatus for scheduling transmissionsin two directions between at least two devices. Thus, although theembodiments are described with references to uplink and downlink, theseterms should not be understood as limiting as the disclosure is notlimited by the directions between a base station and a user terminal.Instead, the invention is applicable to any system where a controlapparatus can schedule transmissions between two or more communicatingentities, wherein the scheduling entity can be seen as being in the“upper” end of the link. For example, this may be the case inapplication where no fixed equipment provided but a communication systemis provided by means of a plurality of user equipment, for example inadhoc networks. Therefore, although certain embodiments were describedabove by way of example with reference to certain exemplifyingarchitectures for wireless networks, technologies and standards,embodiments may be applied to any other suitable forms of communicationsystems than those illustrated and described herein.

The required data processing apparatus and functions of a base stationapparatus, a communication device and any other appropriate apparatusmay be provided by means of one or more data processors. The describedfunctions at each end may be provided by separate processors or by anintegrated processor. The data processors may be of any type suitable tothe local technical environment, and may include one or more of generalpurpose computers, special purpose computers, microprocessors, digitalsignal processors (DSPs), application specific integrated circuits(ASIC), gate level circuits and processors based on multi core processorarchitecture, as non limiting examples. The data processing may bedistributed across several data processing modules. A data processor maybe provided by means of, for example, at least one chip. Appropriatememory capacity can also be provided in the relevant devices. The memoryor memories may be of any type suitable to the local technicalenvironment and may be implemented using any suitable data storagetechnology, such as semiconductor based memory devices, magnetic memorydevices and systems, optical memory devices and systems, fixed memoryand removable memory.

In general, the various embodiments may be implemented in hardware orspecial purpose circuits, software, logic or any combination thereof.Some aspects of the invention may be implemented in hardware, whileother aspects may be implemented in firmware or software which may beexecuted by a controller, microprocessor or other computing device,although the invention is not limited thereto. While various aspects ofthe invention may be illustrated and described as block diagrams, flowcharts, or using some other pictorial representation, it is wellunderstood that these blocks, apparatus, systems, techniques or methodsdescribed herein may be implemented in, as non-limiting examples,hardware, software, firmware, special purpose circuits or logic, generalpurpose hardware or controller or other computing devices, or somecombination thereof. The software may be stored on such physical mediaas memory chips, or memory blocks implemented within the processor,magnetic media such as hard disk or floppy disks, and optical media suchas for example DVD and the data variants thereof, CD.

The foregoing description has provided by way of exemplary andnon-limiting examples a full and informative description of theexemplary embodiment of this invention. However, various modificationsand adaptations may become apparent to those skilled in the relevantarts in view of the foregoing description, when read in conjunction withthe accompanying drawings and the appended claims. However, all such andsimilar modifications of the teachings of this invention will still fallwithin the scope of this invention as defined in the appended claims.Indeed there is a further embodiment comprising a combination of one ormore of any of the other embodiments previously discussed.

1. An apparatus for allocation of resources for wireless communications,the apparatus comprising at least one processor, and at least one memoryincluding computer program code, wherein the at least one memory and thecomputer program code are configured, with the at least one processor,to determine an index for a uplink control resource in accordance with apredefined rule, the determining taking into account an index associatedwith a physical downlink resource and the amount of downlink resourcesto be mapped on the uplink control resource.
 2. An apparatus accordingto claim 1, configured to take into account the lowest index of thephysical downlink resource block.
 3. An apparatus according to claim 1,wherein the index associated with the physical downlink resourcecomprises the index of at least one of an enhanced control channelelement, an enhanced physical downlink control channel and a physicaldownlink shared channel scheduled by means of an enhanced physicaldownlink control channel.
 4. An apparatus according to claim 1,configured to use an offset in determining the index for the uplinkcontrol resource.
 5. An apparatus according to claim 4, configured touse at least one of an antenna port indicator and a scrambling identityin defining the offset.
 6. An apparatus according to claim 4, configuredfor signalling of an offset parameter in the downlink.
 7. An apparatusaccording to claim 4, configured to use the offset for dynamic switchingbetween at least two physical uplink control channel (PUCCH) format1/1a/1b resources.
 8. An apparatus according to claim 1, wherein theamount of downlink resources is indicative of a number of downlinkphysical resource blocks that map to a physical uplink control channelresource.
 9. An apparatus according to claim 1, configured to processindications of the amount of downlink resources based on a configurableparameter.
 10. An apparatus according to claim 1, configured forsignalling of information about the amount of downlink resources in auser equipment specific or cell specific manner.
 11. An apparatusaccording to claim 1, wherein the downlink resource comprises a physicaldownlink shared channel, the apparatus being configured forcommunication of scheduling information for the physical downlink sharedchannel by means of an enhanced physical downlink control channel andfor determining an index for a physical uplink control channel associatewith the physical downlink shared channel.
 12. An apparatus according toclaim 1, configured to determine at least one index for signalling ofautomatic repeat request messages.
 13. An apparatus according to claim1, configured to define a final index for the uplink control resource byapplying at least one further operation to the index determined based onthe index associated with a physical downlink resource and the amount ofdownlink resources to be mapped on the uplink control resource.
 14. Abase station equipment or a user equipment comprising apparatus inaccordance with claim
 1. 15. A method for allocation of resources forwireless communications, the method comprising determining an index fora uplink control resource in accordance with a predefined rule, thedetermining taking into account an index associated with a physicaldownlink resource and the amount of downlink resources to be mapped onthe uplink control resource.
 16. A method according to claim 15,comprising taking into account the index of the lowest physical downlinkresource block.
 17. A method according to claim 15, wherein the indexassociated with the physical downlink resource comprises the index of atleast one of an enhanced control channel element, an enhanced physicaldownlink control channel and a physical downlink shared channelscheduled by means of an enhanced physical downlink control channel. 18.A method according to claim 15, further comprising applying an offset indetermining the index of the uplink control resource.
 19. A methodaccording to claim 18, comprising dynamically switching between at leasttwo PUCCH format 1/1a/1b resources by means of the offset.
 20. A methodaccording to claim 15, wherein the amount of downlink resources isindicative of the number of downlink physical resource blocks that mapto a physical uplink control channel resource.
 21. A method according toclaim 15, comprising configuring the amount of downlink resources bymeans of a parameter.
 22. A method according to claim 15, wherein thedownlink resource comprises a physical downlink shared channel,comprising signalling scheduling information for the physical downlinkshared channel by means of an enhanced physical downlink control channelfor determining an index for a physical uplink control channel thatassociates with the physical downlink shared channel.
 23. A methodaccording to claim 15, configured to determine at least one index forsignalling of automatic repeat request messages.
 24. A computer programcomprising code means adapted to perform the steps of claim 15 when theprogram is run on processor apparatus.